The Polish foreign ministry said in a statement on Monday that Warsaw had replied by underlining “that the ongoing legislative measures, whose overriding aim is to reform the judicial system, are in line with European standards and respond to many years of growing social expectations...”

The foreign ministry added that the commission’s doubts were groundless.

It added in its statement: “In its response, the Polish side has provided exhaustive clarification concerning doubts raised by the European Commission, hoping to continue the dialogue on the merits of the case without any political elements.”

Shot across the bows

The commission said last month it was ready to trigger a formal warning by the EU if Poland dismisses or forces the retirement of Supreme Court judges.

The move followed over a week of street protests in Poland against changes planned to the judicial system by the country’s ruling conservatives.

Poland's governing Law and Justice (PiS) party has said sweeping changes are needed to reform an inefficient and sometimes corrupt judicial system tainted by the communist past, accusing judges of being an elite, self-serving clique often out of touch with the problems of ordinary citizens.

Reforms under fire

But opponents have accused Law and Justice of aiming to stack courts with its own candidates and to dismantle the rule of law.

European Commission President Jean-Claude Juncker said last month that the EU’s executive arm was "determined to defend the rule of law in all our member states as a fundamental principle on which our European Union is built."

Polish Foreign Minister Witold Waszczykowski said at the time that the degree of the commission's interference in the Polish legislative process was unacceptable.

Planned changes to the supreme court and a judicial ethics council were vetoed by Poland’s president but PiS has ploughed ahead with other court reforms.